Form1
Form1
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Form1
Timer_CheckReceiveBuffer
Text_Display
Courier
Timer_ClearStatusMessage
Command_Send
	Send Text
Label_StatusBar
CommStateDCB
CommStat
COMSTAT
ComID
	Form_LoadI
Label_StatusBar
Form10
ScaleWidth&
ShowStatus
OpenComm5
ShowOpenCommError
BaudRate
ByteSize+
Parity
NOPARITY<
StopBitsp
ONESTOPBITX
RlsTimeOutr
CtsTimeOut#
DsrTimeOut
ModeControl
XonCharY
XoffChar
XonLim
XoffLim;
peChar
EofChar
EvtChar
SetCommState
Timer_CheckReceiveBuffer
Interval
Enabled
Truek
Text_Display
Command_Send_Click
crlfc
buffer
	WriteComm
ProcessCommError*
Form_Unload
Cancel
	FlushComm
	CloseComme
Timer_ClearStatusMessage_Timer
CaptionS
Timer_ClearStatusMessage}
False
	ErrorCode
IE_BADID
messageD
IE_BAUDRATEa
IE_BYTESIZE
IE_DEFAULT
IE_HARDWARE
	IE_MEMORY
IE_NOPEN
IE_OPEN
GetCommError
CE_BREAK
ShowMessage
CE_CTSTO%
CE_DSRTO
CE_DNS
CE_FRAME
CE_IOE
CE_MODE
CE_OOPS
CE_OVERRUN/
CE_PTO
	CE_RLSDTO
	CE_RXOVER
CE_RXPARITY
	CE_TXFULL(
Timer_CheckReceiveBuffer_Timer
ReadComm
SelStart
SelText
	StatusMsg
Label_StatusBar_Click
Form_Click
Form_LinkOpen
Text_Display_Change
ComStatusCode
Response[
DefMsgCaption
decided
	currently
* GENERAL DECLARATIONS section of Form1*
COM Device Control Block (DCB) record structure variable
This is a parameter needed by the Windows SetCommState API
function. 
Refer to Form_Load event procedure for an example of
how initialize the COM DCB
COM status variable.
This is a parameter needed by the Windows GetCommError API
function
Identifies the COM port that was opened.
Used by or returned by the Windows API functions
OpenComm, GetCommState, SetCommEventMask, GetCommEventMask,
ReadComm, WriteComm, FlushComm, CloseComm 
Form_Load
* Form_Load event procedure for Form1*
* This is starting point of the program.
* Create the following controls with the
* following CtlNames on Form1:
* Controln
* (Default Name)
 CtlName
 Notes
*   Text1
 Text_Display
 Set the MultiLine property to True*
*   Command1
	 Command_Send
 Set caption property to "Send Text"*
*   Timer1
 Timer_CheckReceiveBuffert
*   Timer2
 Timer_ClearStatusMessaget
*   Label1
 Label_StatusBar
* This event procedure demonstrates how to call the Windows API functions,
* OpenComm and SetCommState to open the COM port.  In this example, then
* COM port is opened as the following equivalent QuickBASIC OPEN COM string:
 "COM1:1200,N,8,1,DS0,CS0,CD0,RS,TB2048,RB2048"
Move the COM status window to the bottom of the form
Show a status message indicating that the COM port is being opened
Opening COM1 ...#
Open COM1 with a 2K input and output buffer
COM device already opened"
Do you wish to use it anyway
Communications Error
Close the com port if the user selected Yes from the message box
Close the COM port if the user decided to use it anywayd
Display a message and terminate the program
if the user decided not to use the COM port
that is currently open
Terminating application"
Communications Abort
Display a critical error message and terminate the program
Error occurred attempting to open the COM port."
  Check connection, settings and rerun the program
Communications Error
Set line settings for the COM port as 1200:N,8,1,CD0,CS0,DS0,RS,TB2048,RB2048c
The following parameter settings represent the default settings set by calling
BuildCommDCB in the Form_Load event procedure.
Set parameters as 1200: N,8,1 
Other possible values include 300, 2400, 4800, 9600, 19200
Other possible values include 4,5,6,70
Other possible values include EVENPARITY, MARKPARITY, ODDPARITY, SPACEPARITY
Other possible values include ONE5STOPBITS, TWOSTOPBITSD
Set timeout period for CD, CS and DS handshake lines respectively.  Values
represent milliseconds.  A value of zero represents an infinite wait effectively
disabling handshaking on that line.  Possible values can range from 0 to 65,535y
for an unsiged integer or -32,768 to 32,767 for signed integers.
Carrier detect or receive-line-signal-detect (CD or RLSD) line (CD0)
Clear-to-send (CTS) line (CS0)
Data-set-ready (DSR) line (DS0)
The following bit flags are combined in the ModeControl field below.  Because)
the following are bit fields they cannot be represented as a field of a Type ... End TypeY
structurew
DCB.fBinary = 1
 Specify binary mode.  Setting this to zero causes an
 EOF character (Chr$(26)) to signal the end of data.
DCB.fRtsDisabled = 1
 Disable request-to-send line (RS).  A zero value enables.
 the request-to-send lineb
DCB.fParity = 0
 Disable parity checking.  A value of 1 enables parity checking
DCB.fOutCtsFlow = 0
 Disable checking of clear-to-send line for output flow control
DCB.fOutxDsrFlow = 0
 Disable checking of data-set-ready (DSR) line for output flow control
DCB.fDummy = 0 + 0
	 Two bit reserved fieldd
DCB.fDtrDisabled = 1
 Disable the data-set-ready line (DTR).  A value of 1 enables DTR.
DCB.fOutX = 0
 Disable XON/XOFF during transmission.e
 A value of 1 enables XON/XOFF.d
DCB.fInX = 0
 Disable XON/XOFF during reception.i
 A value of 1 enables XON/XOFF
DCB.fPeChar = 0
 Disable the replace of parity error characters with the character 
 contained in the PeChar field.  A value of 1 enables replacementt
 of parity error characters with the character contained in then
 PeChar field.
DCB.fNull = 0
 Received null characters are not to be discarded.  A value of 1c
 specifies that null characters received will be discarded.d
DCB.fChEvt = 0
 Reception of the character contained in the EvtChar field doesc
 not signify an event.  A value of 1 indicates that thet
 reception of a character identical to the character contained
 in the EvtChar field signifies and event.
DCB.fDtrFlow = 0
 The DTR line is not used for receive flow control.  A value of 1 
 indicates that the DTR line is used for receive flow control.
DCB.fRtsFlow = 0
 The RTS line is not used for receive flow control.  A value of 1 
 indicates that the DTR line is used for receive flow control.
DCB.fDummy = 0
 Reserved 
1100 0001 
 Binary representationr
 of the above bit settings
	 Hex representation of the abovee
 bit settings 
            DCB.ModeControl = &H83     'Based on the bit settings above
Setting COM State ... #
Set the COM port with the settings as indicated aboveo
Error occurred during initialization of COM settings."
  Check connection, settings and rerun this program"
Communications Error
Start the timer to continuously check the receive buffer
Start the timer only if no errors occurred
Set the focus on the text boxr
Command_Send_Click
* This event procedure demonstrates how to call the Windows*
* API function WriteComm to send data out the COM port.d
* Click event procedure for the command button
* (CtlName: Command_Send) that causes the contents
* of the text box (CtlName: Text_Display) to be sent
* out the COM port.C
* Status information is displayed within caption of a
* label (CtlName: Label_StatusBar).i
Get the data to be sent from the text box.  Note: All*
of the text contained in the text box is sent.
Send the contents of the output buffer out the COM port
Display any communications errors that might have occurred
when attempting to write to the COM port
Form_Unload
* This event procedure demonstrates how to call the Windows API functions*
* FlushComm and CloseComm to close the COM port.
* Close the COM port and end the program.M
Flush the COM transmit and receive buffers.  Note: the return value represents
the success of the FlushComm function call.  Zero = success; Negative = non-successs
The return value is ignored in this example.
Flush all characters in the transmit buffer;
Flush all characters in the receive buffer
Error Closing the COM Port
Communications Error
Timer_ClearStatusMessage_Timer
* Clear the COM status window and disable the timer*
ShowOpenCommError
* Displays a message box for any communications error that
* may have occurred while attempting to open the COM port.
Invalid or unsupported ID"
Unsupported baud rate"
Invalid byte size"
Error in default parameters"
Hardware not present
Unable to allocate queues"
Device not open"
Device already opened"
Communications Error
ProcessCommError
* Display message boxes for any communications
* errors that may occurred when attempting to read from or write to*
* the COM port.  Since more than 1 error can occur when attempting
* to read from or write to the COM port, several messages boxes may
* be displayed.o
* IMPORTANT: If an error occurs during communications, Windows locks
 the COM port.  The COM port can only be unlocked byW
 calling the Windows API function GetCommError.
Character representing a carriage-return
Find out if an error occurs.  Calling GetCommError clears*
the error and causes Windows to unlock the COM port.
Break condition detected
Clear-to-send (CTS) timeout"
Data-set-ready (DSR) timeout
Parallel device is not selected"
Framing error detected
Device I/O error occurred"
attempting to communicate with parallel device
Requested mode is not supported"
Out of paper on parallel device"
Overrun error detected
Timeout attempting to communicate with
parallel device"
Receive-line-signal-detect timeout
Receive buffer overflow"
Parity error detected"
Transmit buffer full
Communications Error
Timer_CheckReceiveBuffer_Timer
* This event procedure demonstrates how to call the Windows*
* API function ReadComm to read information from the COM
* port
Read in up to 2K of data from the COM receive buffer
Read characters waiting in the receive buffer.
If characters were returned in the buffer, display them*
in the text box.  The absolute value of the return value
for ReadComm indicates how many characters were read from the COM.
Display any errors that may have occurred reading from the COM
ShowStatus
* Show a COM status message at the bottom of the form*
Show the message
Set the timer interval to clear the message*